A polyurethane, a polyester, an epoxy resin, and light/electron beam curable resins thereof have been widely used in applications such as paints, coating agents, inks, adhesives, photoresists, sealing agents, binders, and molding materials.
The above-mentioned resins having polyether skeletons, polydiene skeletons, or the like known in the art are not satisfactory in terms of flexibility, compatibility with low polarity resins, uniformity of composition, mechanical strength, solubility, stickiness, bonding property, adhesion, electrical insulation property, weather resistance, water resistance, transparency, results in a pressure cooker test which are the required characteristics of a substrate for an electronic circuit, and the like.
Macromolecular Chemistry and Physics, 198, 3051–3064 (1997) discloses a polyurethane having a poly(2-chloroethyl vinyl ether) skeleton. A resin having a poly(2-chloroethyl vinyl ether) skeleton has problems in stability, for example, that it causes a dechlorination reaction under heating conditions. Further, a 2-chloroethyl vinyl ether, which is the raw material therefor, has become a regulated substance in the Waste Disposal Law and the Living Environment Conservation Ordinance, and accordingly it is considered that the environment is adversely affected thereby.